Motion picture projector



y 1937; A. CALLIER ET AL Re. 20,346

MOTION PICTURE PROJECTOR Original Filed Dec. 21, 1953 INVENTORS 22 ANDRECALLIER FERNAND HEGER By M v 314% ATTORNEYS Reissued May 1 937 UNITEDSTATES PAT/ENT- oFFicE MOTION PICTURE P80112010]! Andre Callier, Gand,and remand Roger, Uecle,

' Belgium Original No. 2,027,875,

Serial No. 703.464, December 21, 1933.

dated January 14, 1938,

ealion for reissue February 24, 1937, Serial No.

127,532. In Belgium:

' 1 Claim.

In order to obviate these inconveniences, the apparatus according to theinvention comprises prismatical combinations which separate from eachother the light beams proceeding from each of the four images, in such away that they are brought'sufiiciently far enough from one another, toallow, for the projection, the use of normal lenses of large relativeaperture.

In particular, when the images are registered on afilm of the normaltype, in such a way that two images are positioned side by side in thebreadth of the film, but require a rotation of 90 when projected, theoptical projecting combination comprises between each image and itscorresponding lens, a right angle roof prism, each of the right anglefaces of which is coupled to an ordinary right angle prism, these twolast prisms being placed in such a way that their free right angle facesare opposed and parallelto the plane of symmetry of the roof prismpassing through the roofs edge.

The drawing annexed to the-present specification shows, by way ofexample, an embodiment of the invention. Figure 1 is a diagrammaticfront view of a projecting apparatus for a film on which the images layside by side and require a rotation of 90.

Figure 2 is a perspective view, ofone of the four optical combinationswhose pu se is to separate and rotate the images in the apparatusrepresented in Fig. 1.

In these two figures the same reference charactors are used to indicatethe same parts.

In the case of Fig. 1,: where the images in, ib, id, if on the film 8require when projected a-rotation of 90, this rotation is effected atthe same 50 time as the separation. In this figure, the separation andthe rotation are realized simultaneously by an optical combination, asshown in Fig. This optical combination includes a right angled isoscelesroof prism Ii whose roof consists 55 oftwo faces lie and lib. Both endfaces lib December 24, 1932 (m. lie-10.0)

and ii) of this roof prism, which are at right angles to one another,are cemented respectively with one of the cathetus faces of a normalright angled isosceles prism, respectivelymarked I8 .and 11., Theseprismsare placed with their free cathetus faces lia and Flu parallel toand on .opposlte sides of the plane of symmetry of the roof prism whichpasses through the edge lig of the roof.

A subject, for instance that represented at 22 in Fig. 2, which isprojected through an optical system according to the invention appearsat 1 the output as indicated at 22'.

' Three rays of light 23, 2!, 2i among those .emitted by this. subjecthave been drawn for representing the paths followed by the rays in thisoptical system.

The position of the image on the free cathetus face lid. of the ordinaryright angled prism IS, on the hypothenuse face lib of the same prism, onthe roof faces lib and lid of the roof prism Ii, on the hypothenuse facellb of the other ordinary right angled prism andv on the free cathetusface lla. of the latter has also been drawn.

The four optical combinations of Fig. 1 are disposed in suehia way thatthe said plane of symmetry is perpendicular to the direction ofprojection and that the prisms H, which are not in front of the imagesin, 91:, 9d, 9] to be projected, are substantially situated in thedirection of the diagonals of the rectangle formed by these four images.The projecting lenses ii, I9, 20 and II are; in this manner,approximately equally separated from each other. The four images 9a,llb, 9d, if on the film are represented in the free cathetus faces lla.as they are positioned relatively to the projecting lenses l8, l9,

Ill and 2|.

What we claim is: A motion picture projector, comprising four projectinglenses for simultaneously projectin four neighboring images of a normalfilm on which these images are registered in such a way that two imageslie side by side in each normal image space of the film but require tobe rotated through 90 when projected, and an optical system between eachimage on the film and the corresponding projecting lens, each opticalsys- 2 f so,s4o 'ot-the roof rim, the two ordinary right angledprojected, one of these right angled M being prisms being arranged withtheir tree cathetus in front of the corresponding image and thelacesparallel to and on opposite sides of the said other in iront oi thecorresponding projecting plane of symmetry, the ordinary right angledlens. '5 prisms of each optical system being disposed in v ANDRE 5 thedirection 0! a diagonal of the rectangle FERNAND HEGER formed by thetour images to be simultaneously v v

